Reduction gears
- Thread starter Matty c
- Start date
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T case or axle ?
15 yrs of discussion on that here via searches but everyone’s opinion is different and we have no information to go on such as type of use or terrain/elevation. Trailer queen? Long-distance driver wheeler? Street queen?
And you forgot option C) turbo via wits end and @NLXTACY
I’ve been running 37‘s with stock gears and the supercharger with less boost for over a decade and happy but in relatively low elevation flattish North Carolina o-3000’.
Old answer 4.88
New anser 3:1 low range .1 under high range
15 yrs of discussion on that here via searches but everyone’s opinion is different and we have no information to go on such as type of use or terrain/elevation. Trailer queen? Long-distance driver wheeler? Street queen?
And you forgot option C) turbo via wits end and @NLXTACY
I’ve been running 37‘s with stock gears and the supercharger with less boost for over a decade and happy but in relatively low elevation flattish North Carolina o-3000’.
Old answer 4.88
New anser 3:1 low range .1 under high range
Last edited:
- Thread starter
- #3
I would like to know which is the best option out of t/f case or axles, also I live in Calgary which is quite elevated and it would be dd and wheelin !
I do have a lot of plans over time so this is only the beginning!!
Thanks for your reply!
Transfer case underdrive high and low reduction gears.
- Thread starter
- #5
What ratio would you go?
RFB
97 FZJ80 LIFTED SC DUAL BATTERIES,37s
i run super heavy nitto muds 37s with 4.88s works well. Almost went to 5.29s till I saw how much beefier 4.88s are. or do the T case or both. what gearing do you have now?/
Define wheeling? Overland and fire roads or playing in the rocks? I’m on 4:88’s and 37’s and for the most part it’s a great combination. But when in the big rocks I wish it was lower.
only one ratio available as far as i know, its the 10% underdrive hi range and the low range crawler gears. I bought Sumo gear sets from cruiser outfitters.
the 10% underdrive hi range has returned my gearing to stock ratios with the 35" tyres. the low range crawlers are there because I had the transfer case apart and they are awesome. even for reversing a heavy trailer up my driveway.
My reasoning for doing the reduction in the transfer case was there are fewer "while you're in there" additional expenses for me, compared to doing the diffs.
If I did 1:4.88 ring and pinions for the 35"s, I would do front and rear rebuild axle kits, brake discs, reco'd callipers, eaton diff locks, camber shims, solid pinion spacers, and something else would probably pop up. as things do. That was way more money than I can spend in one hit, ( I have a sydney house mortgage and 2 kids under 3)
by doing the transfer case I pulled it myself, took it to a workshop with the gear sets and a small parts kit from terrain tamer, had that done and re installed it myself. minimal stuffing around, excellent result. You do have to correct the speedo with a box from Mark's or a yellow box though, as the gearing correction happens before the speedo pickup, not after like when doing the diffs.
My ideal setup with 37 would be 4.88 at the diff, 3.11 low range and 10% over drive For high range.
That’s having your cake and eat it too, after wheeling with rubicon guys I’m envy of their 4:1 transfer low range gear.....while I’m there Harold/Eaton lockers.
That’s having your cake and eat it too, after wheeling with rubicon guys I’m envy of their 4:1 transfer low range gear.....while I’m there Harold/Eaton lockers.
I’m in Calgary too. On 35s with 4.88 and stock tcase gearing. You will be just fine, I’ve ran every trail around here including whipsaw and the Gearing is perfect t the way it is. Send me a pm maybe we can go wheeling
- Thread starter
- #14
Nitro gears ?
I used Yukon, have zero issues. I have used nitro on other builds also with no issues
Nitro works great and not real reported failures. For The transfer gears, most use sumo now and days.
I run 37's km3s / 4.88 in diffs / Tcase - 3.1:1 / UD high range gears - its a good combo
Black Friday is around the corner so keep those savings in mind especially if not in a rush.
Black Friday is around the corner so keep those savings in mind especially if not in a rush.
I have the underdrive gears and 3.1 low range in one of my 80s, stock gearing in the other, and Nitro 4.88s in my 200.
A word of caution: compared to the stock high range gears, the underdrive gears are noisy. Similar in noise level, but a different sound, to mud tires on the road.
Everyone seems to minimize the description of the underdrive gears with “a little gear noise.” I wish someone would have better clarified it before I bought them. Going back and forth with a stock 80 makes it more noticeable. The best I can describe it is a gear whine sound that gets louder with speed like mud tires. If you like the radio loud to drown out your kids fighting, you won’t notice them. If you run ATs because you don’t like the noise of MTs, they will probably bother you. I am trying to get my 80 back to the quiet, comfortable highway ride it was when it was young.
I love my 3.1 gears and my 4.88s, they are both are unnoticed noise wise during daily driving. I am planning on pulling my underdrive gears and putting in 4.88s.
A word of caution: compared to the stock high range gears, the underdrive gears are noisy. Similar in noise level, but a different sound, to mud tires on the road.
Everyone seems to minimize the description of the underdrive gears with “a little gear noise.” I wish someone would have better clarified it before I bought them. Going back and forth with a stock 80 makes it more noticeable. The best I can describe it is a gear whine sound that gets louder with speed like mud tires. If you like the radio loud to drown out your kids fighting, you won’t notice them. If you run ATs because you don’t like the noise of MTs, they will probably bother you. I am trying to get my 80 back to the quiet, comfortable highway ride it was when it was young.
I love my 3.1 gears and my 4.88s, they are both are unnoticed noise wise during daily driving. I am planning on pulling my underdrive gears and putting in 4.88s.
Yes the gear whine. My plan is smoother the interior with sound deadening and bring my wife along to talk my head off
